Syntaxin 1A and 1B display distinct distribution patterns in the rat peripheral nervous system

Neuroscience. 1999 Jan;88(2):437-46. doi: 10.1016/s0306-4522(98)00247-4.

Abstract

Syntaxin 1 has been shown to play an outstanding role in synaptic vesicle exocytosis. Two isoforms of this protein are expressed in neurons, syntaxin 1A and 1B. However, the physiological significance of the occurrence of such closely related isoforms is not still understood. Here, by means of isoform-specific immunocytochemistry, we show that syntaxin 1A and 1B display different patterns of expression in the rat peripheral nervous system. Nerve terminals of sensory neurons reaching the spinal cord were clearly enriched in immunoreactive syntaxin 1A. Both isoforms were detected in cell bodies of sensory neurons at the dorsal root ganglia, although specific immunolabelling displayed very different patterns at the cellular level. Motor endplates and muscle spindles were only immunostained for syntaxin 1B. Syntaxin 1A was mainly associated with nerve fibres reaching small blood vessels. In addition, nerve plexuses of the enteric nervous system showed immunostaining for both syntaxin isoforms. The different distribution pattern of the two neuronal syntaxin isoforms in the rat peripheral nervous system could be related to isoform-specific biochemical properties involved in the exocytotic process.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibody Specificity
  • Antigens, Surface / analysis*
  • Antigens, Surface / immunology
  • Autonomic Nervous System / chemistry
  • Autonomic Nervous System / cytology
  • Calcium-Binding Proteins*
  • Exocytosis / physiology
  • Ganglia, Spinal / chemistry
  • Ganglia, Spinal / cytology
  • Male
  • Membrane Glycoproteins / analysis
  • Membrane Glycoproteins / immunology
  • Membrane Proteins / analysis
  • Membrane Proteins / immunology
  • Motor Neurons / chemistry*
  • Motor Neurons / cytology
  • Motor Neurons / ultrastructure
  • Muscle, Skeletal / innervation
  • Muscle, Smooth, Vascular / innervation
  • Nerve Fibers / chemistry
  • Nerve Tissue Proteins / analysis*
  • Nerve Tissue Proteins / immunology
  • Neurons, Afferent / chemistry
  • Neurons, Afferent / cytology
  • Neurons, Afferent / ultrastructure
  • Peripheral Nervous System / chemistry*
  • Peripheral Nervous System / cytology*
  • R-SNARE Proteins
  • Rabbits
  • Rats
  • Rats, Sprague-Dawley
  • Spinal Cord / chemistry
  • Spinal Cord / cytology
  • Substance P / analysis
  • Substance P / immunology
  • Synaptic Transmission / physiology
  • Synaptophysin / analysis
  • Synaptophysin / immunology
  • Synaptosomal-Associated Protein 25
  • Synaptotagmins
  • Syntaxin 1
  • Tongue / innervation

Substances

  • Antigens, Surface
  • Calcium-Binding Proteins
  • Membrane Glycoproteins
  • Membrane Proteins
  • Nerve Tissue Proteins
  • R-SNARE Proteins
  • Snap25 protein, rat
  • Stx1a protein, rat
  • Synaptophysin
  • Synaptosomal-Associated Protein 25
  • Syntaxin 1
  • Synaptotagmins
  • Substance P